A DESCRIPTION OF THE PROBLEM :
The javadoc signature for method java.util.Optional.orElseThrow() is shown as:

public <X extends Throwable> T orElseThrow(Supplier<? extends X> exceptionSupplier) throws X extends Throwable

The text "extends Throwable" at the very end of that signature is invalid, and should be deleted from the API Specification.

This issue also applies to the method with that same name in classes OptionalDouble, OptionalInt and OptionalLong in package java.util.

The errors are in the current download file named jdk-8u40-docs-all.zip.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
public <X extends Throwable> T orElseThrow(Supplier<? extends X> exceptionSupplier) throws X


ACTUAL -
public <X extends Throwable> T orElseThrow(Supplier<? extends X> exceptionSupplier) throws X extends Throwable



URL OF FAULTY DOCUMENTATION :
https://docs.oracle.com/javase/8/docs/api/java/util/OptionalInt.html#orElseThrow-java.util.function.Supplier-